The present invention relates to plows fitted on vehicles for moving snow, dirt, sand, gravel and other plowable, excavatable materials and, more particularly, to a plow for snow and other materials for use with pickup trucks and other vehicles having plow wings which are individually adjustable for both extension of the main plow and forward angling for positioning the plow to prevent snow or other plowed material from slipping off the ends of the plow.
A wide variety of snow plows for pickup trucks and other vehicles are available and in use. These include straight bladed plows of the type shown in U.S. Pat. No. 3,250,026, and center-hinged, V-plows of the type shown in U.S. Pat. Nos. 4,074,448 and 4,658,519. Other straight bladed plows have been devised with one or both ends being slidably extendable as shown in U.S. Pat. No. 2,218,512; U.S. Pat. No. 3,807,064; and Swedish 323,974. Yet other plows have included straight blades with pivotable, non-extendable ends as shown in U.S. Pat. Nos. 4,145,825 and 3,477,151. At least one plow is shown in EPO 140,139 having permanently forwardly angled plow ends, which forwardly angled plow ends include slidable extensions wherein the entire plow swings from side to side so as to angle the entire plow left or right.
While each of the above types of prior known plows is useful in one or more situations, the overall flexibility for use of these plows has been limited. For example, for truck mounted plows which must be transported from one site to another for clearing snow or other plowable materials, it is necessary that the plow be short enough to allow transport on public highways which have limited lane width. However, when actually engaged in plowing, it is very helpful to have a greater length for the plow so that larger areas of the parking lot or other site can be cleared of snow more quickly. Yet another problem encountered is when large amounts of snow or other plowable material must be pushed or carried with the plow from one area of a clearing site to another such as the side of a parking lot. Many of the above mentioned plows allow the snow or other material being cleared to slip off the ends of the plow thereby requiring additional time and work to completely clear the site.
Plows have been proposed which provide adjustable wings which are extendable and retractable and may be pivoted forwardly from their extended positions to form a generally U-shaped plow. For example, such plows are disclosed in U.S. Pat. Nos. 5,638,618 and 5,899,007. The plow moldboard of these plows has an opening or slot therealong to connect the plow wings and pivot hinges to the plow assembly, such that the plow wings are slidable along a front surface of the plow between an extended and retracted position.
Many existing, prior known plows have, therefore, failed to provide a plow with sufficient flexibility to handle the varying needs encountered in plowing using pickup trucks or other vehicles, especially when such vehicles must be driven on public highways, or when excavating or grading using a bulldozer, grader or the like. Such needs include a short enough plow length to allow transportation on public highways, a long enough length for fast, efficient clearing of a job site, and the carrying or pushing of snow, dirt, sand, gravel or the like from one area to another without allowing snow or other material to slip off the plow ends. In addition, plows should be as light in weight as possible while sufficiently strong to withstand the various forces imposed thereon during plowing of various materials, should allow for proper visibility during use as well as when moved to a non-use position on the vehicle, and should allow ease in repair or replacement of those parts subject to high wear during plowing use. All of these results should be accomplished while minimizing the size and space required for the plow in each of its arrangements.
The present invention provides a plow having adjustable wings on its ends which can be adjusted to varying positions to allow transport on public highways, to provide increased plow length for fast, efficient clearing of snow or other materials being plowed, and to allow carrying or pushing of plowable material from one area to another without the plowed material slipping off the plow ends. The present plow may be configured in various arrangements to handle each of these situations while minimizing the size and space required by the plow when in position on the vehicle. The present plow also allows adjustment to meet these various situations from a remote position in the cab of the vehicle without external, hands on adjustment.
According to an aspect of the present invention, a plow assembly for vehicles comprises a plow, a support for attaching the plow to the vehicle, an extendable plow wing, and at least one actuator for moving the plow wing between an extended and retracted position along a rear surface of the plow and for pivoting the plow wing forwardly with respect to the plow. The plow includes first and second ends, a front material engaging surface, and the rear surface opposite said front surface. The plow wing has inner and outer ends, a front material engaging surface, and a rear surface opposite the front surface. The plow wing is mounted for sliding movement along the rear surface of the plow at the first end between a retracted position, in which the outer end of the plow wing is adjacent the first end of the plow, and an extended position, in which the outer end of the plow wing is spaced outwardly of the first end of the plow with the front surface of the plow wing being generally aligned with the plow front surface. The plow wing includes a hinge and is pivotally mounted on the hinge for movement between an aligned position in which the front surface of the plow wing is generally aligned with the front surface of the plow, and a forwardly angled position in which the front surface of the plow wing extends at an angle to the plow front surface. The actuator is operable to move the plow wing between the retracted and the extended positions and is further operable to move the plow wing between the aligned position and the forwardly angled position.
Preferably, the plow assembly includes a plow wing at each end of the plow. Both plow wings are movable between the extended and retracted positions and further movable between the aligned and forwardly angled positions with respect to the plow. Optionally, the plow assembly may include two pair of actuators, such as hydraulic cylinders or the like. Each pair of actuators is operable to move one of the plow wings with respect to the plow. One of the actuators of each pair is operable to move the respective plow wing along the rear surface of the plow between the extended and retracted positions, while the other actuator of the pair is operable to move or pivot the respective plow wing about the hinge between the aligned and forwardly angled positions. Preferably, the actuators are controlled such that the second actuator is not actuated to pivot the plow wing until after the plow wing or wings has/have been fully extended to the extended position by the first actuator.
According to another aspect of the present invention, a plow assembly for vehicles comprises a plow, a support frame for attaching the plow to the vehicle, a pair of plow wings at opposite ends of the plow, a pair of slides, which are movable along a rear surface of the plow, and at least two actuators, at least one of the actuators being operable to move a respective one of the plow wings relative to the plow. The plow includes a front material engaging surface, which provides a generally continuous surface for engaging and moving material, such as snow, dirt, sand or the like. The plow is pivotally mounted on the support frame for movement about a first, generally vertical pivot axis from a centered position extending generally transverse to a longitudinal axis of the vehicle to a series of angled positions in which the plow is angled to the left or right of the centered position. Each of the plow wings preferably has a cross-sectional contour corresponding to the plow and is mounted for sliding movement along a rear surface of the plow. Each of the plow wings is movable between a retracted position, in which an outer end of the plow wing is adjacent its respective end of the plow, and an extended position, in which the outer end of the plow wing is spaced outwardly from its respective end of the plow. Each of the plow wings is generally aligned with the plow front surface as it moves between the retracted and extended positions. Each plow wing also includes a hinge and is pivotally mounted on the hinge for movement between the extended position and a forwardly angled position in which the wing front surface extends at an angle to the plow front surface. Each plow wing and corresponding hinge is mounted on and movable with the respective slide, which is slidably movable along the rear surface of the plow. Each of the plow wings is operable independently of the other plow wing such that the plow wings are independently movable between the respective, retracted, extended, and forwardly angled positions.
Optionally, the plow includes two pair of actuators, whereby one pair of the two pair of actuators is operable to move one of the plow wings, and the other pair of actuators is operable to move the other plow wing. Preferably, one of the actuators of each pair of actuators is operable to move the slide, and thus the hinge and plow wing, along the rear of the plow between the extended and retracted positions, while the other of the actuators of each pair is operable to move or pivot the plow wing about the hinge between the extended and forwardly angled positions.
Accordingly, the plow assembly of the present invention provides numerous advantages over prior known plows. The present plow assembly has sufficient flexibility to handle varying needs including being short enough in length when not extended to allow transport on public highways without projecting into adjacent lanes, being extendable to a sufficient length to allow fast, efficient clearing of snow or other material being plowed from a large area, and yet being configurable with either one or both of the extendable ends angled forwardly for highly efficient carrying and/or pushing of plowed material from one location in the area being plowed to another without the plowed material slipping off the plow ends. All of these functions are accomplished by the present plow assembly with minimal size and space due to its compact and efficient construction. The plow may be centered for pushing or carrying of snow or other plowed material, or angled to one side or the other for moving snow or other material to the side of the vehicle supporting the plow. One or both plow wings at the ends of the plow may be extended or pivoted forwardly independently or together, while the entire plow may be centered or angled to one side or the other with one or both of the plow wings extended or pivoted forwardly. In either case, the plow wings at either end of the main plow are independently extendable and movable to a forwardly angled position via remote control from the cab of the vehicle by means of actuators, such as hydraulic fluid cylinders, mounted along the back of the plow. Either a single fluid cylinder or a pair of fluid cylinders may be mounted to move each plow wing with respect to the plow. The main plow blade provides a generally continuous, uninterrupted surface, since the plow wings and slides are mounted at and movable along the rear surface of the plow, such that the plow does not require any openings or movable components at its front, material engaging surface to move or pivot the plow wings with respect thereto. This avoids the possibility of dirt, ice, or other materials becoming lodged in the movable mechanisms of the plow wings, since these mechanisms are positioned entirely behind the uninterrupted moldboard of the plow. The continuous front surface of the plow thus prevents the plowed material from being packed into the moving components, such as the hinges and slides, as the plow engages such materials, even when the plow wings are partially or fully extended and/or pivoted relative to the plow. This not only may improve the operation of the plow wings when plowing or excavating, but may also increase the life cycle of the plow wings and their associated components.
In addition, both the main plow and the extendable wings pivot forwardly on a horizontal axis in the event an obstacle is encountered during plowing. Further, when the plow wings are extended, if the vehicle is moved in reverse and a quantity of snow or other material being plowed engages the rear surface of either plow wing, either a latch mechanism, the main plow blade, or a fluid cylinder maintains the plow wing in alignment with the plow blade and prevents movement to the forwardly angled position until desired. In addition, the extendable, adjustable plow of the present invention has been designed in a highly compact, lightweight manner allowing use on a wide variety of pickup trucks, utility vehicles, tractors and other vehicles as well, including bulldozers, graders, or other excavation or construction vehicles. It may be supported at the front of a vehicle via the preferred support frame or by means such as vertical supports positioned behind the plow assembly such as in a road grader. In addition, the plow assembly of the present invention is rugged, strong and highly durable to allow use in harsh weather or environmental conditions over an extended period of time.
These and other objects, advantages, purposes and features of the invention will become more apparent from a study of the following description taken in conjunction with the drawings.